The present invention relates to a method of side transmission through unidirectional clutch and the clutch for such purpose, and more particularly to a method of side transmission through unidirectional clutch that enables easy production of quality-enhanced unidirectional clutch at reduced cost.
Unidirectional clutch that is known for use in sports goods industry usually requires an additional holder that is mounted to an outer periphery of the clutch in a tight-fit manner, such as in the commercially available KK series sold under the brand MORSE and RC, FC, RCB and FCB thin-shell series of different brands. Alternatively, the clutch are mounted in the holder by engagement of key slots provided at an outer circumferential surface of the clutch with keys provided on the holder, such as in the B series sold under the brand MORSE. After being fixedly mounted in the additional holder, the clutch provides one-way transmission through braking elements thereof Since the above- mentioned conventional clutch must have a matched holder connected to it in the tight-fit manner, there is no way to effectively reduce the space required by the clutch and the holder. Moreover, the problem such as the difficulty in effective control of complicate and precised fit of the clutch in the holder also exists in the practical use of the clutch.
Taking the commercially available thin-shell one-way bearing series RC, FC, RCB and FCB (that have a shell thickness less than 2 mm) as an example, the production thereof involves high precision and many complicated procedures, and the fact that a bad yield in terms of matched clutch and holder is still higher than 25%. When the one-way bearing is mounted in the holder in the tight-fit manner and a tight-fit interference thereof is larger than 0.05 mm, the thin-shell one-way bearing would deform and results in poor transmission. On the other hand, when the tight-fit interference is smaller than 0.02 mm, the thin-shell one-way bearing that is subjected to a force to be transmitted tends to slide in the holder and fails to effectively transmit the force. As a matter of fact, it is not easy to meet the strict requirement of proper interference and good match of the clutch with the holder by improving production management and quality control in the process of manufacturing the thin-shell one-way bearings. It is known that all kinds of parts and accessories are produced with an acceptable range of tolerance. And, to enable the one-way bearing to be tight-fitted in the holder with an cumulated tolerance of all related parts and/or accessories thereof still within an acceptable range, it is inevitable to make the bearing and the holder at a very high manufacturing cost.
In addition to the KK and B series of thin-shell one-way bearings sold under the brand MORSE, there are still many other equivalent one-way bearings, such as NF, NFS and NSS series from different manufacturers that all are high-precision products requiring multiple complicated procedures to complete them. These products are expensive and not suitable for incorporating in mass-produced goods that are intended for general consumers.
It is therefore tried by the inventor to develop a method of side transmission through unidirectional clutch to eliminate the additional holder that has to be tight-fitted to the conventional one-way bearing.